Rail posts used to construct railings for structures such as decks, balconies, etc. must withstand loading. In a typical configuration, the post may be attached to a structural member, for example, a rim joist, using one or more bolts which extend partially or fully through the post and the structural member. The post may provide a lever action that can intensify the force, e.g., the loading the post itself exerts at the attachment point. The railing, and the posts comprising the railing, may be subject to other loading forces which may include leaning loads during normal use and intermittent loading which may be severe. An example of the latter is impact loading of the railing from snow sliding off roofs during the winter season.
The rail posts used to construct railings on structures such as decks, balconies, etc., may be notched prior to assembly to the horizontal structural member, for example, the rim joist of a deck. The notch in the rail post may significantly weaken the strength properties of the posts. Checks or cracks may propagate along the grain lines at the notch as the material, typically lumber, of the post ages, dries and shrinks.
Other instability in the railing may occur over time, due to aging of the wood or other materials used to construct the railing and/or structure to which the railing is attached, expansion and contraction of the respective railing and/or structure which may result in weakening of the railing and/or loosening of the railing from the structure, which may result in the need to replace, repair, or reinforce the railing and/or the structure.